Normally, upon printing an image sensed by a digital camera, the following processes are required. That is, an image stored in the digital camera is read by a personal computer (to be referred to as a PC hereinafter), and is printed by a connected printer using an application running on the PC.
That is, the flow of image data is DSC→PC→printer, and possession of the PC is indispensable. Also, the PC must be started to print an image stored in a DSC.
In consideration of such situation, some proposals in which a DSC and printer are directly connected, and a print instruction is issued on a display normally equipped on the DSC (to be referred to as photo direct print hereinafter) have already been made.
Merits of use of the photo direct print system are easy print without starting a PC and low system building cost since a PC is not indispensable. Upon connecting a DSC to a printer, a display normally equipped on the DSC is used as means for giving various instructions and, especially, for confirming an image to be printed. Hence, a printer does not require any special display used to confirm an image, and the cost can be further reduced.
In general, a DSC stores a sensed image in a detachable memory card (called a CF card, smart media card, or the like). Such memory card has a storage size of, e.g., about 64 MB or 128 MB, and stores several ten to 100 images since the resolution of recent DSCs is as high as several million pixels.
In other words, when the maximum number of images that can be stored is reached, a new image cannot be sensed unless a free area is assured by erasing some or all stored images.
Therefore, important images must be printed before they are erased. However, if image data as sources of printouts are erased, those original image data can never again be used (an image scanner may be used, but an image having quality as high as digital data as a 100% original image cannot be restored).
A PC user can store those images in a hard disk of the PC, but a user who does not possess any PC cannot do it. Even for the PC user, he or she must connect a DSC to a printer and to a PC, resulting in troublesome operations.